Military Technology 04/2021

NGSW hopefuls NGSW is an unusual programme, in that it involves three competing pairs of guns chambered for a new calibre and three very different new ammunition technologies, all of which are required to use the US Army’s new 6.8mm XM1186 projectile. To achieve the required lethality at ranges up to 600m, including the penetration of body armour, without needing extra-long barrels, the ammunition must generate chamber pressures higher than any previously used in comparable infantry small arms. A further requirement is a weight saving in the range of 30-40%, that will avoid placing an extra burden on the soldier despite the ammunition’s extra power. The weapons must also include a powered accessory rail to support an electro-optical fire control system that includes a ballistic computer and a suite of sensors, and must therefore have provision for a battery. Major powers only replace their mainstream small arms every few decades, and the adoption of a new calibre at the same time is even rarer. By October, however, the US Army may have chosen re- placements for both the M4 carbine and the M249 Squad Automatic Weapon (SAW) light machinegun, initially for its close combat units. The Next Generation Squad Weapon (NGSW) effort is centred on the Next Generation Squad Carbine (NGSC) and the Next Generation Squad Automatic Rifle (NGSAR), both chambered for a new 6.8mm round, with greater range and lethality than 5.56x45mm ammunition. With procurement of around 120,000 guns anticipated over the next five years, NGSW may not be a gigantic programme, but its influence will be global. For example, Israel Weapon Industries (IWI) is following the programme carefully, according to Ronen Hamudot, Corporate VP for Marketing and Sales. “We believe that the small arms market will adjust to 6.5mm and 6.8mm calibres as a result of the growing need for increased lethality, and IWI’s weapons are ready to adopt them,” he told MilTech . Inevitably, the US adoption of a new round has implications for US allies in terms of the hard-won interoperability and logistics benefits that flowed from NATO’s 1970 decision to adopt 5.56x45mm as the standard assault rifle round. Alone, NGSW is sufficient to disrupt the small arms market, but the US military is also looking for a new ‘medium’ machinegun in a 0.338 Norma Magnum (8.6x63.3 mm) calibre, intermediate between the 7.62x51mm and 12.7x99mm rounds. At this point, a brief foray into the evolution of squad light machine- gun thinking is worthwhile. In the post-war period, and into the Cold War, new designs emerged to take advantage of the also new 7.62x39mm and 5.56x45mm assault rifle rounds. Contrasting approaches to the design of these weapons emerged at this time, exemplified by two Soviet squad light machineguns in the form of the Degtyaryov RPD and its short order replacement, the Kalashnikov RPK. The first was belt-fed, full-automatic only, fired from an open bolt and can be usefully thought of as a miniature GPMG. The second was essentially an AKM assault rifle with a heavier receiver, a longer and heavier barrel, a bipod and a larger capacity maga- zine. The RPK fired from a closed bolt and, like the RPD, lacked a quick- change barrel. Open-bolt firing and quick-change barrels are features that support sustained fire by mitigating heat build-up. Both styles of weapon are in use by western forces, and there are examples of both offered as candidates for the NGSAR component of NGSW. Peter Donaldson Recent Developments in Small Arms and Ammunition 46 · MT 4/2021 Feature Offered in three barrel lengths, IWI’s new CARMEL assault rifle uses a conventional layout in a design strongly focused on ergonomics and ambidexterity, combined with low maintenance costs. (Photo: Israel Weapon Industries)